title: Waist circumference and waist/hip ratio are better predictive risk factors for mortality and morbidity after colorectal surgery than body mass index and body surface area.
abstract: OBJECTIVE
  To determine whether body fat distribution, measured by waist circumference (WC) and waist/hip ratio (WHR), is a better predictor of mortality and morbidity after colorectal surgery than body mass index (BMI) or body surface area (BSA).
  
  
  BACKGROUND
  Obesity measured by BMI is not a consistent risk factor for postoperative mortality and morbidity after abdominal surgery. Studies in metabolic and cardiovascular diseases have shown WC and WHR to be better outcome predictors than BMI.
  
  
  METHODS
  A prospective multicenter international study was conducted among patients undergoing elective colorectal surgery. The WHR, BMI, and BSA were derived from body weight, height, and waist and hip circumferences measured preoperatively. Uni- and multivariate analyses were performed to identify risk factors for postoperative outcomes.
  
  
  RESULTS
  A total of 1349 patients (754 men) from 38 centers in 11 countries were included. Increasing WHR significantly increased the risk of conversion [odds ratio (OR) = 15.7, relative risk (RR) = 4.1], intraoperative complications (OR = 11.0, RR = 3.2), postoperative surgical complications (OR = 7.7, RR = 2.0), medical complications (OR = 13.2, RR = 2.5), anastomotic leak (OR = 13.7, RR = 3.3), reoperations (OR = 13.3, RR = 2.9), and death (OR = 653.1, RR = 21.8). Both BMI (OR = 39.5, RR = 1.1) and BSA (OR = 4.9, RR = 3.1) were associated with an increased risk of abdominal wound complication. In multivariate analysis, the WHR predicted intraoperative complications, conversion, medical complications, and reinterventions, whereas BMI was a risk factor only for abdominal wall complications; BSA did not reach significance for any outcome.
  
  
  CONCLUSIONS
  The WHR is predictive of adverse events after elective colorectal surgery. It should be used in routine clinical practice and in future risk-estimating systems.
authors.affiliation: *Colorectal Surgery Unit and Colorectal Tumor Board, Cliniques Universitaires Saint-Luc, Brussels, Belgium †Department of Abdominal Surgery, Gasthuisberg University Hospital, Leuven, Belgium ‡Department of Coloproctology, Western General Hospital, University of Edinburgh, Edinburgh, United Kingdom §Department of Digestive Surgery, Hôpital St-Joseph, Gilly, Belgium ¶Plateforme technologique de Support en Méthodologie et Calcul Statistique, Université Catholique de Louvain, Louvain-La-Neuve, Belgium ‖Division of Colon and Rectal Surgery, Mayo Clinic, Rochester, MN, USA **Department of Colorectal Surgery, Oxford University Hospitals, Oxford, United Kingdom ††Service of Visceral Surgery, Geneva University Hospitals, Geneva, Switzerland ‡‡Department of General and Digestive Surgery, Hôpital St-Antoine, Paris, France.
authors.forename: Alex H
authors.initials: AH
authors.lastname: Kartheuser
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Leonard
authors.forename: Freddy
authors.initials: F
authors.lastname: Penninckx
authors.forename: Hugh M
authors.initials: HM
authors.lastname: Paterson
authors.forename: Dimitri
authors.initials: D
authors.lastname: Brandt
authors.forename: Christophe
authors.initials: C
authors.lastname: Remue
authors.forename: Céline
authors.initials: C
authors.lastname: Bugli
authors.forename: Eric
authors.initials: E
authors.lastname: Dozois
authors.forename: Neil
authors.initials: N
authors.lastname: Mortensen
authors.forename: Frédéric
authors.initials: F
authors.lastname: Ris
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Tiret
mesh_terms: D000368:Aged; D015992:Body Mass Index; D001830:Body Surface Area; D003107:Colorectal Surgery / Q000401:mortality*; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007431:Intraoperative Complications / Q000401:mortality; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D011183:Postoperative Complications / Q000401:mortality; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors; D055105:Waist Circumference; D049629:Waist-Hip Ratio